About the book

Contents

About the book, and changes in the New Edition 8

PART	SECTION	UNIT/FOCUS
1 The computer	1 Introduction	1 What is a computer? 16 Focus A Contextual reference 21 2 History of computers 23 Focus B Suffixes 29
	2 Description	3 Characteristics 36 Focus C Organizing information 42 4 Computer capabilities and limitations 46 5 Hardware and software 52 Focus D Prefixes 58
	3 Kinds of computers	6 Mainframes 64 Focus E Listing 69 7 Minicomputers 72 8 Microcomputers 77 Focus F Making comparisons 83
2 Computer components	4 The processor	9 The Central Processing Unit 94 Focus G Time sequence 99 10 The Control Unit and the Arithmetic-Logical Unit 102 Focus H Giving examples 107

PART	SECTION	UNIT/FOCUS
2 Computer components	5 Memory	11 Primary and secondary memory 111 Focus I Adding information 116 12 Types of memory 119 Focus J Giving an explanation or a definition 124
6 Input and output devices	13 Cards, readers and keyboards 129 Focus K Classifying 136 14 Tapes and tape drives 141 15 Disks and disk drives 148 Focus L Contrasting 257 16 Printers 160 17 Terminals 769 Focus M Cause and effect 176
3 Data processing	7 Programming	18 Steps in problem solving 186 19 Computer arithmetic 191 20 Flowcharting 197 21 Programs and programming languages 207 Focus N Making predictions 214
8 Computer-related topics	22 Time sharing versus batch 218 23 Careers 224

Projections Extended reading passage 229 Glossary 233

About the book

explaining, defining, classifying, predicting, etc. Secondly, it teaches students reading skills such as locating information, finding the main idea of a text, and following the development of an argument. And thirdly, it provides the reader with up-to-date basic information about computers and how they operate, through the subject matter presented in each reading passage. The texts cover a wide range of topics: from the memory to computer arithmetic, from program design to on-line processing.

What changes are there in this New Edition?

Because computer technology is developing so rapidly, some of the information in English for Computer Science, although only published in 1984, was already out of date by 1986.

You will find these changes in the New Edition:

1 The reading passages have been revised and facts corrected wherever necessary. The changes occur in Units 8 Microcomputers; 11 Primary and Secondary Memory; 13 Cards, Readers and Keyboards (new title); 18 Steps in Problem Solving and 21 Programs and Programming Languages. The exercise types remain the same, with appropriate adjustment of vocabulary and numbering. All Focus sections - teaching grammar and vocabulary - remain unchanged.

2 The final section, Projections, has been developed into a longer reading passage. This covers the newest applications of computer technology and gives students an opportunity to read extensively.

3 The accompanying Answer Book has been revised.

4 There is now a listening cassette for use as a pronunciation guide with the New Edition of English for Computer Science. It contains all the reading passages together with the pronunciation of all the terms listed in the Glossary.

What will students learn from this book?

A growing number of students of computer science and people working with computers have an immediate and specific need to acquire a reading knowledge of computer science in English.

To read effectively in a second or foreign language requires both an understanding of the grammar and vocabulary of that language and also the development or application of reading skills. This book helps students in three main ways. Firstly, it provides exercise material on formal aspects of language, such as grammar and vocabulary. The fourteen Focus sections present and practise language functions most readily associated with the English used in computer science:

Who is the book intended for?

English for Computer Science has been written for people who are studying computer science or related subjects in universities, colleges and technical schools, and also for in-company training programs where computer personnel need to improve their understanding of English.

The book can easily be used for self-study by individuals who want to make use of computers privately or for their careers. In this case the accompanying Answer Book will provide the necessary guidance. We would suggest as a study method that the student working alone should always attempt to answer the questions before turning to the Answer Book. You can check your answers at the end of each exercise or at the end of a whole unit, but don't be tempted to work with the Answer Book open! Several short study sessions per week are more useful than one long period. Try to do some revision of previous units at least once a week.

If English for Computer Science is used purely as a reading course, it should take between 45-60 hours to complete the work, depending, of course, on the students' proficiency in English. However, the book could equally well be used as an integral part of a course which also includes listening, speaking and writing. In that case the course would, necessarily, be considerably longer.

How much computer science must the teacher know?

Since the book is written with the assumption that many readers will have little or no previous knowledge of computer science, it follows that the teacher need not have much technical background in the field. It is advisable, however, that the teacher understands the concepts and terminology introduced in each unit in order to be as much a resource person as possible, to answer queries that may arise in class or at least to direct the students to the appropriate place to find an answer. This type of dialogue and exchange ensures real communication in the classroom, where the students understand that the teacher doesn't have to know

PARTI

The Computer

Computers are electronic machines that process information. They are capable of communicating with the user, of doing five

kinds of arithmetic operations, and of making three kinds of

decisions. However, they are incapable of thinking. They accept

data and instructions as input, and after processing the

information, they output the results.

When talking about computers, both hardware and software

need to be considered. The former refers to the actual

machinery, whereas the latter refers to the programs that

control and coordinate the activities of the hardware.

The first computer was built in 1930 but since then computer technology has evolved a great deal. There are three different

kinds of computers in use today: the mainframe, the

minicomputer, and the microcomputer. However, the dividing

line between these has become rather blurred; a modern micro

is often as powerful as a mainframe was ten years ago. All three

have one thing in common - they operate quickly and accurately

in solving problems.

depending on the mediumused in inputting information) reads the information into the computer.

UNII I 101

What is a computer?

When you read the following text, you will probably meet words and expressions that are new to you. First try to understand their meaning from the context - read the same passage a few times. When you have read the whole text, check new words in a dictionary. Most of the words in bold typeface are explained in the Glossary at the end of this book.

[1] A computer is a machine with an intricate network of electronic 1

circuits that operate switches or magnetize tiny metal cores. The switches, like the cores, are capable of being in one of two possible states, that is, on or off; magnetized or demagnetized. The machine is capable of storing and manipulating numbers, letters, and characters. 5 The basic idea of a computer is that we can make the machine do what we want by inputting signals that turn certain switches on and turn others off, or that magnetize or do not magnetize the cores.

[2] The basic job of computers is the processing of information. For this

reason, computers can be defined as devices which accept information 10 in the form of instructions called a program and characters called data, perform mathematical and/or logical operations on the information, and then supply results of these operations. The program, or part of it, which tells the computers what to do and the data, which provide the information needed to solve the problem, are kept inside the computer 15 in a place called memory.

[3] Computers are thought to have many remarkable powers. However,
most computers, whether large or small have three basic capabilities.
First, computers have circuits for performing arithmetic operations,
such as: addition, subtraction, division, multiplication and 20

exponentiation. Second, computers have a means of communicating
with the user. After all, if we couldn't feed information in and get
results back, these machines wouldn't be of much use. However, certain
computers (commonly minicomputers and microcomputers) are used to
control directly things such as robots, aircraft navigation systems, 25

medical instruments, etc.

[4] Some of the most common methods of inputting information are to use punched cards, magnetic tape, disks, and terminals. The computer's input device (which might be a card reader, a tape drive or disk drive,

For outputting information, two common devices used are a printer which prints the new information on paper, or a CRT display screen which shows the results on a TV-like screen.

[5] Third, computers have circuits which can make decisions. The kinds of 35
decisions which computer circuits can make are not of the type: 'Who
would win a war between two countries?' or 'Who is the richest person
in the world?' Unfortunately, the computer can only decide three
things, namely: Is one number less than another? Are two numbers
equal? and, Is one number greater than another? 40

[6j A computer can solve a series of problems and make hundreds, even
thousands, of logical decisions without becoming tired or bored. It can
find the solution to a problem in a fraction of the time it takes a human
being to do the job. A computer can replace people in dull, routine
tasks, but it has no originality; it works according to the instructions 45

given to it and cannot exercise any value judgments. There are times
when a computer seems to operate like a mechanical 'brain', but its
achievements are limited by the minds of human beings. A computer
cannot do anything unless a person tells it what to do and gives it the
appropriate information; but because electric pulses can move at the 50

speed of light, a computer can carry out vast numbers of arithmetic-logical operations almost instantaneously. A person can do everything a computer can do, but in many cases that person would be dead long before the job was finished.

T F

I I I I 8. Computers can make any type of decision they are asked to.

I I I I 9. Computers can work endlessly without having to stop to rest unless there is a breakdown.

Exercises

Main idea

Which statement best expresses the main idea of the text? Why did you eliminate the other choices?

I I 1. Computers have changed the way in which many kinds of jobs are done.

I I 2. Instructions and data must be given to the computer to act on.

I 1 3. Computers are machines capable of processing and outputting data.

I I 4. Without computers, many tasks would take much longer to do.

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